1969 - Chattanooga is the Most Polluted City in the United States

thumb Chattanooga Worst Pollution article 1969 300The Department of Health, Education and Welfare named Chattanooga the most polluted city in the nation.  Chattanooga had a heavy industrial base, and in 1969, unregulated emissions from industries, railroads, and coal furnaces caused high concentrations of particulate matter.  Chattanooga's topography compounded the problem by causing temperature inversions (during which cold air flows over the mountains into the valley and is trapped--with the pollution--by a layer of warm air).

These factors, along with deteriorating scenic views and rising national claims of pollution-related sickness, prompted the citizens, government, and industrial leaders in Chattanooga and Hamilton County to take drastic measures. They proposed air pollution control regulations. These measures had been debated for years, but suddenly became a priority.

1972 – Hamilton County Achieved the Local Standardthumb Clean Air Billboard 1970s 300

Chattanoogans approved a new Air Pollution Control Ordinance in late 1969. This aggressive legislation, which created the current Air Pollution Control Board and Bureau, set restrictions on almost all pollution-causing activities in the county, including placing limits on visible emissions from local industries. The Ordinance set an attainment date for October 14, 1972. Incredibly, in that three-year period, every major pollution source in Hamilton County was in compliance, at a cost of over $40 million. This tremendous achievement received national attention and was celebrated with "Clean Air Week" during October 1972.

1989 - Achieved the Federal Standard

Clean Air Week 1985The city celebrated in 1989 when Chattanooga's air quality met all federal health standards. It was a huge milestone for both the Air Pollution Control Board and Bureau and Hamilton County.  Chattanooga continued to meet the federal health standards until federal regulations were tightened in 1997.

1997 – Federal Regulations were Tightened

While Chattanooga's air was cleaner than it had ever been, the growing awareness of the link between air pollution and illness caused the government to make air quality standards more stringent.  The new standards put Chattanooga in jeopardy of losing their "attainment" status.  The EPA, working with environmental groups and air pollution organizations, created a way to achieve cleaner air faster -  areas destined to be out of compliance with federal standards were allowed to form Early Action Compacts (EAC).  These compacts were agreements to take voluntary measures to clean up the air. Chattanooga's EAC went into effect in 2004.

Our state, county and city took several progressive steps toward achieving attainment as a result of the EAC, including:

  • county-wide vehicle emissions testing
  • seasonal burning (allowed from October-April of each year)
  • vapor recovery systems for fuel tankers
  • Pollution Solution public outreach program
  •  diesel school bus retrofitting
  • lowering truck speed limits on the interstate

Hamilton County, using the methods outlined in the EAC, was able to reduce air pollution, increase air quality, and was designated in "attainment" with federal standards for ozone. (We were declared out of attainment for particulate in early 2005.)

2008 – EPA Lowers the Air Quality Standards Again

Just as Hamilton County met the new federal standard requirements, the EPA decided that the regulations were not stringent enough to reduce pollution-related illnesses, and lowered the standard again.


skyline market st bridge 2011Hamilton County's air is cleaner than ever, but every day we work towards meeting the federal requirements.  Without the help of our citizens, it would be impossible to keep our air clean.  We encourage everyone to reduce air pollution by reducing vehicle trips through carpooling, walking or riding a bike, or taking mass transit.  Other steps citizens can take include fueling their vehicles after 6 p.m., not mowing their lawns on high pollution days, and choosing alternatives to burning brush (wood chipping, brush pick-up services).

Without the cooperation among government, industry, and concerned citizens, the progress Chattanooga has made would not have been possible.  Please help us make air pollution history in Chattanooga and Hamilton County now and for generations to come.

Download our history book, A History of Air Pollution Control in Chattanooga and Hamilton County.